1. Field of the Invention
The present invention relates to an induction detecting type rotary encoder which measures a rotary angle of an object by using magnetic flux coupling between wirings provided in a rotor and a stator.
2. Description of the Related Art
A rotary encoder includes a stator which is provided with a transmitting coil and a receiving coil and a rotor which is provided with a magnetic flux coupling coil for causing magnetic flux coupling with the transmitting and receiving coils. In the case where a rotary encoder is applied to a hand tool such as a micrometer, a decrease in size thereof needs to be realized by integrating plural tracks (the transmitting coil, the receiving coil, and the magnetic flux coupling coil) for generating signals having different wavelengths.
For example, a rotary encoder disclosed in JP-A-2006-322927 includes first and second transmitting coils which are sequentially provided from the inside so as to be concentric about a rotary shaft and first and second receiving coils which are sequentially provided from the inside so as to correspond to the first and second transmitting coils and to be concentric about the rotary shaft. In addition, the rotary encoder disclosed in JP-A-2006-322927 includes first and second magnetic flux coupling bodies which are formed so as to be concentric about the rotary shaft and cause magnetic flux coupling with the first and second receiving coils.
In order to further improve precision, it is desirable to have a configuration in which crosstalk between adjacent tracks is maximally suppressed.